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arXiv · 2407.13487

Anisotropic cosmology in Bumblebee gravity theory

Pranjal Sarmah·Umananda Dev Goswami
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Abstract

The Bumblebee vector model of spontaneous Lorentz symmetry breaking (LSB) in Bianchi type I (BI) Universe to observe its effect on cosmological evolution is an interesting aspect of study in anisotropic cosmology. In this study, we have considered a Bumblebee field under vacuum expectation value condition (VEV) with BI metric and studied the cosmological parameters along with observational data. Further, we have studied the effect of anisotropy and the Bumblebee field in cosmic evolution. We have also studied the effect of both anisotropy and Bumblebee field while considering the Universe as a dynamical system. We have found that there are some prominent roles of both anisotropy and the Bumblebee field in cosmic evolutions. We have also observed an elongated matter-dominated phase as compared to standard cosmology. Moreover, while studying the dynamical system analysis, we have also observed the shift of critical points from standard $\Lambda$CDM results showing the anisotropy and the Bumblebee field effect.

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Pranjal Sarmah, Umananda Dev Goswami. 2024-07-18. Anisotropic cosmology in Bumblebee gravity theory. https://doi.org/10.1016/j.dark.2025.102057

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